IM 6.2.5 identify returns wrong dpi values with PNG and BMP

[el_supremo]

Your problem may be related to the bug I have described in my post "BMP resolution units".
If you interpret 28.34 as being pixels per centimetre then multiplying by 2.54cm/in gives 72 pixels per inch. So that number is correct provided that you realize that it is pixels per centimetre rather than per inch.

Pete